It is common to provide an electrical connector that mounts in an opening of a wall which may be in an appliance. The connector has a connector element with a threaded shaft that is projected through the opening in the wall, and a clamping member that is threaded onto the shaft. If threads with a small helical angle are used, then friction between the tightened threaded parts resists unscrewing. Locking washers are sometimes used, which add friction when the threaded elements are tightened.
In many applications, it is desirable to use bayonet threads, which are threads having a large helical angle, to permit rapid attachment. Most bayonet threads extend by less than a complete turn around the axis. Bayonet threads have the advantage that they allow elements to be rapidly fastened by turning one element by less than a complete turn, or only slightly greater than a complete turn, until the threads are completely tightened. However, with the large helical angle of a bayonet thread, they are subject to rapid loosening, especially if subjected to vibrations. Ordinary lock washers are generally not sufficient to prevent loosening. An electrical connector with parts that could be threadably connected using a large helical angle thread such as a bayonet thread, and which resisted accidental loosening, would be of value.